The present invention relates generally to a cleaning and polishing apparatus and method used in the disk drive industry. More specifically, the present invention relates to a cleaning and polishing apparatus and method used in the manufacture of a head gimbal assembly.
Thin film heads are used for reading or writing data onto a recording layer of a data storage disk. Typically, the head xe2x80x9cflies xe2x80x9d above the surface of the disk at a very low xe2x80x9caltitudexe2x80x9d. The height of the air gap between the head and the disk is usually measured in fractions of a micron. The low height of the air gap causes an air bearing to be formed.
For a disk that stores data using magnetic effects, the head usually includes a radio frequency coil for transmitting and receiving a magnetic field to write and read in the recording layer. For disks that store data using optical effects, the head may include an objective lens to focus a light beam at the recording layer.
Along with the evolution of the disk industry, the surface cleanliness of read-write heads has become one of the most critical concerns. With low-flying heads, dust in the environment is a serious problem. Dust particles can cause catastrophic xe2x80x9chead crashes xe2x80x9ddestroying the head and disk. Also, significant amounts of dust can accumulate on the head to interfere with the magnetic or optical effects. Contaminants may cause a disk driver to malfunction or even fail to spin up.
Classical wash, rinse and dry technology using an aqueous chemical substance and ultrasonic agitation can not provide adequate cleaning efficiency for a head""s air bearing surface. More effective contamination removal methods to ensure that components and drives always remain as clean as possible are needed.
U.S. Pat. No. 5,467,238 issued to Neville K. Lee et al on Nov. 14, 1995, disclosed a cleaning apparatus for cleaning read/write heads used for accessing data stored on a recording disk of a disk drive. The cleaning apparatus had a mounting base positioned adjacent to the disk. The base includes a ratchet mechanism for rotating a cleaning pad mounted thereon. The rotary or linear actuator arm used to position the read/write head activates the ratchet mechanism. The ratchet mechanism rotates the cleaning pad while the actuator unloads the read/write head from the disk. A loading ramp is used to vertically position the read/write head relative to a cleaning surface of the cleaning pad. This conventional cleaning apparatus is more complicated in structure, lower in efficiency, and is used only after assembly of a disk drive, making it unsuitable for use in the mass production of the heads.
A new kind of cleaning and polishing apparatus and method for cleaning the heads of a head gimbal assembly to eliminate contamination of the heads by dusts or particulates is disclosed. In accordance with one aspect of the present invention, a cleaning and polishing apparatus for cleaning a head of a head gimbal assembly (HGA) may have a frame, a plurality of carriers for locating and holding a plurality of HGAs, a plurality of polish fingers under the carriers and fixed on a loading base, a cloth attached to said polish fingers, and a plurality of press-pins on each of the carriers. The HGAs may have a face and a slider with an air-bearing surface (ABS) to be polished and directed downwards. The cloth may act as a polish medium to provide a plurality of polish surfaces on which the HGAs are polished and cleaned. The press pins press on a HGA""s flexure to provide proper friction between the slider ABS and the polish surface.
According to another embodiment, a pneumatic cylinder unit is combined with the carriers. The pneumatic cylinder unit, controlled by a programmable controller, may move the carriers, as well as the plurality of HGAs. The pneumatic cylinder unit may move back and forth in X and Y directions according to a customized program. The solution may be sufficiently agitated by the motion of a cylinder unit to promote dissolution action. Also, a polish tank containing a cleaning solution, may be provided on the top of the frame. The cleaning solution is recirculated through a pump and a filter canister with an effective filter cartridge. The filter canister may filter off the insoluble, suspended contaminants and particles in the solution so that the slider ABS will not be re-contaminated. A thermostatically controlled strip heater may heat the solution to a desired working temperature. The contaminants may be scrubbed off into the solution through solubilization, emulsification, chemical action by a detergent, etc. The temperature, kind, and concentration of the chemical substance of said solution may be selected to achieve maximum cleaning effectiveness. The apparatus and method of the invention is suitable for the removal of dusts, oils, fingerprints, and other organic and inorganic contaminants in the form of both particulate and thin-film.